A former Orthodox priest and archbishop has been sentenced to eight months in jail for sexually assaulting an altar boy in Winnipeg during the 1980s.

A Manitoba judge handed down the decision Wednesday morning against Seraphim Kenneth Storheim, 68, calling his conduct "deplorable and a gross breach of trust" and saying the lasting effects of the crime are serious.

Storheim appeared emotionless for much of the hearing, but about a dozen of his supporters who showed up to court were visibly shaken.

Almost immediately, Storheim's lawyer, Jeff Gindin, said his client is appealing the decision.

"There will be plenty" of grounds for appeal, Gindin said.

"Essentially we feel [Court of Queen's Bench Justice Christopher Mainella] analyzed credibility with errors all the way through."